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TY - CONF AU - Chae, Y.-C. AU - Keil, J. ED - Koscielniak, Shane ED - Satogata, Todd ED - Schaa, Volker RW ED - Thomson, Jana TI - Control of Collective Effects by Active Harmonic Cavity in an MBA-based Light Source with Application to the PETRA Upgrade J2 - Proc. of IPAC2018, Vancouver, BC, Canada, April 29-May 4, 2018 C1 - Vancouver, BC, Canada T2 - International Particle Accelerator Conference T3 - 9 LA - english AB - Based on the reference lattice for PETRA IV* we investigated collective effects with non-zero current. Out of many possibilities we firstly computed the intrabeam-scattering (IBS) effects on the emittance as well as lifetime as a function of current. The result indicated that PETRA IV would benefit from the reduced peak current when the harmonic cavity lengthens the bunch. The operating point of harmonic cavity was explored by tracking simulations as well as analytic formula. In order to compute the energy spread and bunch length we had used the known impedance function of the APS**. In this way more realistic estimation of IBS effects was expected. However, because of the complex nature of PETRA IV lattice, which includes achromatic cells for undulators, arc cells of octants and straight sectors for damping wigglers, we simplify the longitudinal dynamics by assuming the ring made of 92 multi-bend-achromat (MBA) cells. The optics is approximated as a linear-chromatic transfer map enabling fast tracking and the ring impedance is concatenated into the one location. The detailed collective effects with and without harmonic cavities are presented in the paper. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1433 EP - 1435 KW - cavity KW - impedance KW - emittance KW - lattice KW - synchrotron DA - 2018/06 PY - 2018 SN - 978-3-95450-184-7 DO - 10.18429/JACoW-IPAC2018-TUPMF074 UR - http://jacow.org/ipac2018/papers/tupmf074.pdf ER -